Mud gun



E. E. BROSIUS Dec. 29, 1936.

MUD GUN Filed May 29, 1934 INVENTOR Patented Dec. 29, 1936 UNITED STATES PATENT OFFICE 6 Claims.

This invention relates to mud guns of the type used in stopping the tap hole at the base of furnaces after the molten charge has been withdrawn, and more particularly to that type of gun wherein the piston for ejecting the mud from the barrel of the gun is mechanically operated, as distinguished from mud guns of the type wherein the piston is fluid operated.

Heretofore, it has been proposed to mechanically propel the piston by means of a screw mechanism. In my Patent No. 1,889,433, dated November 29, 1932, I have disclosed a mud gun wherein the piston is operated through 'a rack and pinion drive, the piston rod being in the form of a double rack with pinions engaging this rack and geared to a reversible motor for operating the pinions.

While the construction shown in my said patent, employing a rack and pinion drive, has been highly successful, and while the screw drive also has been successful to some extent, both types of apparatus are open to certain objections. The first is that the drives are absolutely rigid and unyielding. A sudden shock or jar or an unexpected overload may result in the stripping of a gear tooth, or of a worm tooth in the case of a screw drive. In order to definitely insure against any such stripping of the teeth, the parts are made very heavy so as to insure a more than adequate overload strength. A second objection with apparatus of this type is that some of the mud will work past the piston and it will come into engagement with the driving mechanism. If the rack is not properly designed to avoid the accumulation of this mud therein, the mud will collect in the rack teeth and very materially shorten the useful life of the equipment, and make the frequent repair of the equipment necessary. With a screw-operated drive, the mud works into the screw and into the driving mechanism and also causes considerable difiiculty and wear and makes frequent repairing necessary.

In apparatus of this kind, some reducing gear is needed between the driving motor and the piston. The present invention results in a lighter reduction gear being employed and in less strain being placed on the reducing gears.

According to the present invention, it is contemplated that motion shall be transmitted to the piston through the use of flexible cables rather than through the use of rigid driving elements. This drum and cable driving system is far less susceptible to injury by mud and foreign matter. The construction of the various parts is considerably simp1ified. The cable system iself can be used as a part of the speed reducing mechanism, and the cable system will more readily resist sudden shocks and sudden conditions of overload, or resistance to movement of the piston, than will the gear or worm types of drives 5 heretofore used. Not only is the cable mechanism much better adapted to the operation of the mud gun, but it is also considerably cheaper.

The invention may be readily understood by reference to the accompanying drawing, in which Figure 1 represents a top plan view of a mud gun embodying my invention, and

Figure 2 represents a longitudinal section through part of the apparatus, part of the apparatus being shown in elevation, the section being a broken section.

In the drawing, 2 designates a barrel of any usual or preferred construction, the barrel shown being generally similar to that disclosed in my said Patent No. 1,889,433. At the forward end of the barrel is a discharge spout or nose 3. The barrel is provided with a charging opening 4 having a cover 5 for normally closing this opening. Movable along the barrel 2 is a piston 6. The piston itself is of the construction commonly employed in mud guns of this character. The piston is carried on and propelled by a longitudinally extending I-beam member 1, the member 1 constituting the piston rod. In the particular construction shown, the I-beam is illustrated as having the web of the beam vertical and the flanges horizontal. The Web of the I-beam is illustrated as being cut away adjacent the forward end of the beam to receive a pulley 8. Similarly the rear end of the I-beam is illustrated as having an opening 9 formed in the web thereof. In this opening is another pulley Ill. The pulley I 0 is carried on a vertical pin I l which passes through the top and bottom flanges of the I-beam, the I-beam being slotted to receive the ends of this pin. The upper and lower ends of the pin are received in the arms of a yoke l2, this yoke being provided with a bolt l3 which bears against the end of the I-beam and which provides a longitudinal adjustment for the pulley Ill. 5

To the rear of the barrel 2 is a casting or other suitably formed supporting structure designated generally as M. This supporting structure I4 carries two vertical spindles l5 and I6, one of these being at each side of the longitudinal axis of the piston rod 1. The spindle l5 has a drum ll thereon and the spindle l6 has a drum l8 thereon. These two drums are at opposite sides of the piston rod 1. Above the drums ii and IS, the spindles are provided with inter-meshing gear wheel 2 I.

gears I9 which are both of the same diameter. The spindle I5 is of greater height than the spindle I6 and extends up into a gear housing 23. On the upper end of the spindle I5 within the gear housing is a large gear 2I. This gear is engaged by a small driving pinion 22, the driving pinion 22 being on a shaft 23, the upper end of which is provided with a bevel gear 24. The bevel gear 24 is engaged by a pinion 25 on a shaft 26, the shaft 26 being provided with a gear wheel 21 that meshes with a pinion 28 on the armature shaft of a reversible driving motor 29.

At 30 is a cable having one end anchored at 3| to the fixed supporting frame I4 and having its other end anchored to the drum II, this cable passing over the pulley 8 carried in the piston rod. A second cable 32 has one end anchored at 33 to the stationary supporting frame I4 and has its other end anchored to the drum I8. This cable passes around the periphery of the adjustable fixed pulley ID at the rear end of the piston rod. The cables 30 and 32 are preferably in the form of flat steel cables as shown, these flexible fiat steel cables being obtainable. These fiat cables are preferred to round cables because they can be wrapped around the drums I1 and I8 more advantageously, and a considerably greater strength of cable can be obtained in a limited space. i

In Figures 1 and 2, the piston is shown in its retracted position. Assuming that the barrel is charged with mud and it is desired to expel this mud into a furnace opening, the motor 29 is energized. The motor drives the pinion 28, gear 27, and through the bevel gears 25 and 24, rotates the pinion 22. The pinion 22 in turn rotates the When the gear 2I revolves, the spindle I5 is rotated. The inter-meshing gears I9 0n the spindles I5 and I 6 causes the two drums I1 and I8 to rotate in opposite directions but at the same speed. The motor is operated in such manner as to cause the drum I8 to wind up the cable 32. As the cable 32 winds up, the piston rod 1 will be forced forward, and as it moves forward the drum I? will pay out the cable 30. Since one end of the cable 32 is anchored and the other end is attached to the drum while the intermediate portion passes over the pulley I0, it will be seen that the provision of the cable provides a 2 to 1 speed reduction with a consequent increase in power, the mechanism of this, of course, being similar to the ordinary block and tackle principle.

When the piston has reached the forward limit of its travel, and it is desired to retract the piston, the motor 29 is driven in the opposite direction, in which case the drum IT winds up the cable 30 and the drum I8 pays out the cable 32.

In Figure 2, I have shown a rod 35 attached to the piston and having a finger 36 secured to its outer end. Secured to the supporting frame structure I4 on brackets provided for the purpose is a rod 31 on which the finger 36 is slidably supported. As the piston 6 is pushed forward, the finger 36 travels along the rod 31, thus indicating to the operator the extent of travel of the piston.

From the foregoing detailed description of the specific form of the invention which has been shown, it may be seen that the present invention provides a very simple mechanism for transmitting motion from the motor to the piston. Due to the fact that the cable arrangement as described provides a 2 to 1 reduction in speed and a corresponding increase in power, the reducing gear train can be made relatively light and more simple than with other types of drive, and will be subject to less severe strains. The mechanism itself is one which is not likely to be affected by mud and foreign matter which may get into the operating mechanism, and the cables being flexible and very slightly elastic, can absorb sudden shocks and overload strains much more readily than can rigid gear teeth or screw driving mechanisms. Moreover, while the drive is superior, it is also much more economical.

By making the pulley longitudinally adjustable, the degree of slack or tension on the cables 32 and 30 can be controlled. If too much slack occurs, the pulley I0 can be adjusted closer to the rear of the piston rod 1, whereas if the cable system is too tight, sufiicient slack can be developed by loosening up this one pulley.

While I have illustrated and described one preferred embodiment of my invention, it will be understood that this is merely illustrative of the invention and that various changes and modifications may be made within the contemplation of the invention and under the scope of the following claims. It is further intended that the word cable shall contemplate flexible ropes or chains of any character having sufficient strength to be adapted to this purpose.

I claim:

1. A mud gun comprising a barrel, a piston operable in the barrel, a drum and cable mechanism for moving the piston in one direction, a second drum and cable system for moving the piston in the opposite direction, the two systems being symmetrically arranged with one of the drums on one side of the longitudinal axis of the barrel and the other on the other side of the longitudinal axis of the barrel, and a common driving means for both systems.

2. A mud gun comprising a barrel, a piston reciprocable in the barrel, a rigid extension at the rear of the piston having a sheave adjacent the forward end thereof and another sheave adjacent the rear end thereof, a pair of winding drums one of which is located at each side of the said extension, and a cable system passing around said sheaves and said drums for operating the piston.

3. A mud gun comprising a barrel, a piston reciprocable in the barrel, a rigid extension projecting rearwardly from the piston, said extension having a sheave therein adjacent one end thereof, a second sheave adjacent the opposite end thereof, a pair of oppositely winding drums one of which is located at each side of the said extension, a supporting structure for said drums, a cable having one end secured to one drum and having one end anchored to said supporting structure and passing around one of said sheaves, a second cable secured to the' other drum and anchored to said supporting structure and passing around the other sheave, and driving means for simultaneously operating both drums in reverse directions.

4. A mud gun comprising a barrel, a piston in the barrel, an I-beam member extending rearwardly of the piston and constituting an operating extension, a pair of longitudinally supported sheaves carried by said I-beam, a supporting structure at the rear of the barrel, a pair of drums on the supporting structure, one of said drums being at each side of the I-beam, said drums being located between the limits of movement ofthe two sheaves, a cable secured to one drum passing around one sheave and dead-ended to the supporting structure, a second cable secured to the other drum, passing around the other sheave and dead-ended to the supporting structure, gearing connecting the two drums, and a driving mechanism for said gearing.

5. A mud gun comprising a barrel, a piston reciprocable within the barrel, an operating extension projecting rearwardly from the piston, a driving motor, a reducing gear connected with the motor, a pair of drums operatively connected with the reducing gear and driven thereby in opposite directions and cables engaging the drums and the said extension for reciprocating the piston, one drum being positioned at each side of the operating extension.

6. A mud gun comprising a. barrel, a piston reciprocable in the barrel, an operating extension projecting rearwardly from the piston, a supporting structure at the rear of the barrel, a pair of drums on the supporting structure, one drum being at each side of the said extension, one drum of which is located in a horizontal position at each side of said extension, reversible means including gearing between the two drums for simultaneously driving both drums in opposite directions, a sheave in said extension located forwardly of said drums, a second sheave on said extension located rearwardly of said drums, the distance between said sheaves being at least as great as the distance of travel of the piston, a cable secured to one drum passing around one of said sheaves and 10 anchored to the supporting structure on the side of the extension opposite to the side on which said drum to which it is connected is located, and a second cable secured to the other drum, passing around the other sheave and being anchored 15 to said supporting structure on the side of said extension opposite the side Where said first cable is anchored.

EDGAR E. BROSIUS. 

